Riyadh: A shooting at a Shiite mosque in eastern Saudi Arabia killed three people and wounded others on Friday during prayers, security officials and a witness said, the latest violence to strike the region.

The attack struck the Imam Reza Mosque in the neighbourhood of Mehasin during prayers. Images on social media showed wounded laying on the mosque's floor.

The security officials said the three dead was an initial toll. They spoke on condition of anonymity as a formal announcement had yet to be made.

Witness Mohammed al-Nimr told The Associated Press that security forces and ambulances quickly surrounded the mosque. He said that it was a shooting and that worshippers stopped the attacker from detonating a suicide bomb belt.

Saudi state media did not immediately report on the attack.

Shiites in Saudi Arabia previously have been targeted in attacks by the Islamic State group in the kingdom. Earlier this month, Saudi officials also executed a prominent Shiite cleric from the region, raising tensions in the area.